Hello @AllenShull
Thanks for posting this in the global Instructure Community!
I am sorry that you are seeing this issue when grading on your iOS device. I did not see that there was anything listed on this in the Known issues page for Canvas.
I have not experienced this issue myself... but if you are consistently seeing it happen, it might be best to contact Support and have them take a closer look. They might need to have you provide them with a screen recording of the issue and any links to where it is happening so that they can attempt to replicate the behavior.
Let us know what you find out on this!
-Colton